Coronavirus Sars-CoV-2/Covid-19 Megathread

[Iormlund]

What I meant with New York isn't that we ignore it, just that it's not a terribly useful comparison because it's one of the five worst outbreaks in the world - and I don't know why that is, I don't know what factors made those areas so bad (New York, Bergamo, Guayaquil and Lima) because they don't seem to have much in common. If anything I think the interesting question is why is New York like those, what happened that made it so bad rather than why is Florida/California/Washington (and I think Washington's a really interesting example) not like New York. Because the worst bits of Spain, the UK, France, Belgium are not like New York.

Of course all those areas have something in common: millions of daily commuters crammed into public transport.

I'm going to go on a limb here and say that people in Florida might not be as tightly packed as in the NY metro area.

[Sheilbh]

Of course all those areas have something in common: millions of daily commuters crammed into public transport.

I'm going to go on a limb here and say that people in Florida might not be as tightly packed as in the NY metro area.

Really - New York, Bergamo, Guayaquil and Lima do they all have millions of daily commuters on public transport?

I agree for the sort of second tier of bad outbreaks - London, Lombardy, Ile-de-France with Madrid and Castilla La Mancha at the top end. But even then in that category of bad outbreaks there are other regions that seem a bit odd - Valle d'Aosta, Navarra, La Rioja.

If it was New York, London, Madrid, Milan at the top I'd agree. But it's not. And both groups looka little strange so I think there's more than density/public transport.

[Iormlund]

Of course all those areas have something in common: millions of daily commuters crammed into public transport.

I'm going to go on a limb here and say that people in Florida might not be as tightly packed as in the NY metro area.

Really - New York, Bergamo, Guayaquil and Lima do they all have millions of daily commuters on public transport?

I agree for the sort of second tier of bad outbreaks - London, Lombardy, Ile-de-France with Madrid and Castilla La Mancha at the top end. But even then in that category of bad outbreaks there are other regions that seem a bit odd - Valle d'Aosta, Navarra, La Rioja.

If it was New York, London, Madrid, Milan at the top I'd agree. But it's not. And both groups looka little strange so I think there's more than density/public transport.

Bergamo is just 40 km from Milan. It's a bit disingenuous to treat them as separate outbreaks.

Similarly, if you take a look at the seroprevalence data, the biggest Spanish cluster is located in Madrid and adjacent provinces (Guadalajara, Segovia, Cuenca ...) which are deeply interconnected with the city.
La Rioja had a severe outbreak early on, when members of a Roma clan broke quarantine and infected a lot of people at a funeral. It has a below average antibody presence, however. And Navarra's just a bit above average.

Guayaquil and Lima are big cities, with almost 3 and 10 million inhabitants respectively. And being relatively poor not that many people will commute on their own by car.

[DGuller]

None of this is relevant.  Most useful distributions in real life have a domain that starts at zero.  This is has nothing to do with them being left-censored at zero. 

Plenty of relevant and useful distributions aren't cutoff at zero: wealth can be negative (debt), net income can be negative, economic growth can be genitive, inflation can be negative, among many others. Some are cutoff at zero and its pretty common to take that in account when performing an analysis on the data set, such as through the use of a tobit. It can be misleading to using a straight mean when dealing with a variable that is bounded at zero but unbounded in the other direction. 

It's a minor point, I only pointed it out because it seemed like you were throwing some technical term randomly to make it look like it supports a dubious assertion.

I'm glad we resolved that mistaken concern

I don't think we resolved anything at all, but I'm not going to belabor the point.  Hopefully next time you'll be a little more careful on the trigger with sophisticated-sounding non sequiturs, at least the ones relating to statistics.

[Sheilbh]

Bergamo is just 40 km from Milan. It's a bit disingenuous to treat them as separate outbreaks.

[...]

Guayaquil and Lima are big cities, with almost 3 and 10 million inhabitants respectively. And being relatively poor not that many people will commute on their own by car.

So the data I've been looking at is just excess mortality rather than infection or serological studies. But here's the thing - within Bergamo is wildly above Milan. That's why I think it's worth looking at them separately because they've got such different outcomes and Bergamo is the smaller city without, say, a metro system. Obviously they're connected - but why are the outcomes so different?

And I totally get that on Guayaquil and Lima (which might not have peaked) - but they've had an almost 300% increase in excess mortality - why is that so much worse than Manaus (150%) or Santiago (100% - though not clear that Santiago has peaked)? As I say Latin America is the centre of the pandemic now, but it's not clear that being a big relatively poor city is sufficient - outside of Latin America there are examples like Jakarta (55% and trending down).

But again I just don't see anything in common with those areas and New York which have all had such huge increases. The other question for me is why was New York so much worse hit than other big, dense cities with lots of public transport. Even if you exclude the successful cities (Singapore, Hong Kong, Tokyo, Seoul), New York had 2-3 times the excess mortality rate of places like London, Milan, Madrid etc.

The only thing that they might have in common is if the disease arrived earlier than understood and was circulating for a long while? Are they maybe more "internally dense"?

Similarly, if you take a look at the seroprevalence data, the biggest Spanish cluster is located in Madrid and adjacent provinces (Guadalajara, Segovia, Cuenca ...) which are deeply interconnected with the city.
La Rioja had a severe outbreak early on, when members of a Roma clan broke quarantine and infected a lot of people at a funeral. It has a below average antibody presence, however. And Navarra's just a bit above average.

Yeah again - so I've just looked at excess mortality and some of these regions are obviously a lot less populated than others so a "small" outbreak in comparison with Madrid can have a big impact. But, for example, Navarra's excess mortality was about 85% above average - only Madrid, Castilla La Mancha and Catalonia are worse - but the absolute numbers are far, far smaller.

I don't have any conclusions,  by the way. I just think don't think there's a clear common thread running through the outcomes of this. I don't know how much density or public transport or age profile or overcrowding or poverty matters and how they interact. And it feels like you get radically different results if you just look at Europe, or the Americas, or Asia (MASKS!) or if you look at it globally. I imagine there are people looking into this and it'll be really interesting but to be honest the only bit that seems intuitive and what I'd expect with common threads (for me at least) is Europe.

[DGuller]

A lot of the differences could just be the luck of the draw.  It's an unsatisfying conclusion, but sometimes it's the right one that even many professionals don't consider heavily enough. 

Maybe NYC got a super-spreader early on that other cities didn't get.  In the early phase of the outbreak, when everyone is caught with their pants down, the spread is essentially exponential, and with a really high rate of growth at that.  One trait of exponential growth with some element of luck involved is that your luck early on has an incredibly leveraged impact on eventual outcome. 

The difference between a disaster city and a non-disaster city could really be as simple as the fact that patient zero in the former infected 10 people, and patient zero in the latter infected 2.  The luck of the latter city bought it time, so that when they did enter the lockdown, they were a week or two behind on uncontrolled spread simply because the chose their patient zero wisely.

[The Minsky Moment]

The "Section 8" housing that serves much of New York's poorer residents crams people into dense high rises; these large buildings may have only a single properly working elevator at any given time.

[Monoriu]

Few places can claim to have a higher density of people or high rises than Hong Kong.  We have like 1,200 cases and 6 deaths so far. 

[DGuller]

Could it be central AC systems?  I remember early on there was a conference in Boston where something like 100 attendees got infected.  Either they all got infected from highly gregarious superspreader, or it was the hotel's central AC that did the superspreading.

[viper37]

Of course all those areas have something in common: millions of daily commuters crammed into public transport.

I'm going to go on a limb here and say that people in Florida might not be as tightly packed as in the NY metro area.

Really - New York, Bergamo, Guayaquil and Lima do they all have millions of daily commuters on public transport?

I agree for the sort of second tier of bad outbreaks - London, Lombardy, Ile-de-France with Madrid and Castilla La Mancha at the top end. But even then in that category of bad outbreaks there are other regions that seem a bit odd - Valle d'Aosta, Navarra, La Rioja.

If it was New York, London, Madrid, Milan at the top I'd agree. But it's not. And both groups looka little strange so I think there's more than density/public transport.

the race factor might have played a role.  African americans in general tend to not view health services in a positive way, due to past interactions.  It's possible latinos equally distrust health officials due to the later one.
See this:https://www.grunge.com/220418/the-crazy-true-story-of-the-tuskegee-syphilis-experiment/
and this:
https://www.thoughtco.com/u-s-governments-role-sterilizing-women-of-color-2834600
You have a densed city, lots of commuters who will often distrust the health care services provided by the state, it's a recipe for disaster.

had to this the fact that NY might have been a little late to confine its population, and you get to a situation where the hospital network is highly strained, near collapse and then people die en masse.  When you reach that point, it doesn't matter anymore who's trusting the system or not, or wether they arrive too late at the hospitals or not.

Also, NY lacked respirators and PPEs quite early in the pandemic, that means a lot of staff get infected and pass on the disease to other patients.

[viper37]

Few places can claim to have a higher density of people or high rises than Hong Kong.  We have like 1,200 cases and 6 deaths so far. 

By the time it reached HK, you knew it was coming and people were quickly tested and confined, wether they agreed or not.  If you look a little south to where you live, you'll see the city of Wuhan and can see what happens when the disease isn't stopped in its tracks very early on.

[viper37]

Could it be central AC systems?  I remember early on there was a conference in Boston where something like 100 attendees got infected.  Either they all got infected from highly gregarious superspreader, or it was the hotel's central AC that did the superspreading.

I think it's a little of everything.

[Monoriu]

Few places can claim to have a higher density of people or high rises than Hong Kong.  We have like 1,200 cases and 6 deaths so far. 

By the time it reached HK, you knew it was coming and people were quickly tested and confined, wether they agreed or not.  If you look a little south to where you live, you'll see the city of Wuhan and can see what happens when the disease isn't stopped in its tracks very early on.

The virus hit HK in January 2020, earlier than it hit New York.  My point is there is no reason why London, New York etc perform worse than Hong Kong.  These places have better technology, more wealth, more time to prepare, lower density, etc etc. 

[Eddie Teach]

Masks.

[Iormlund]

Few places can claim to have a higher density of people or high rises than Hong Kong.  We have like 1,200 cases and 6 deaths so far.

You guys were using masks though. In the US or Spain the authorities were telling people masks were useless, because they didn't have enough PPE for frontline workers.